To obtain a drying and moisture-controlling powdery agent capable of improving the defects of conventional drying and moisture-controlling methods where warm air is used for long time, because rise and cereals have respectively different properties, are different in water contents due to their kinds, harvest times, harvest methods, etc., have water contents unsuitable for storage and transportation in many cases, and therefore require treatments for adjusting the moisture to a state suitable for the storage and transportation, wherein the defects of the conventional methods comprise the deterioration in the flavors, tastes, etc., of the rice and the cereals due to the temperature and flow of the warm air.

This drying and moisture-controlling powdery agent only for rice and cereals is produced by kneading starch as a main raw material with water and an vegetable oil, converting the kneaded starch into α-starch, drying the treated mixture and subsequently finely grinding the dried product. The obtained drying the moisture-controlling agent is extremely rapid in the absorption of water, can release water, does not adhere to the surfaces of the rice and cereals, can easily be separated from the rice and the cereals, can repeatedly be used, when used under sufficiently controlled states, and does not cause the generation of a lingering scent, because the main raw material is the α-starch.